METHOD OF FORMING PROTECTIVE SKULL IN BLAST FURNACE HEARTH Russian patent published in 2004 - IPC

FIELD: ferrous metallurgy; blast furnace processes; melting cast iron in blast furnaces. SUBSTANCE: proposed method includes delivery of titanium-containing skull-forming additive to furnace hearth through channel of cast iron cage together with tap-hole loam by means of gun for closing the cast iron tap hole. Skull-forming additive ground to size of lesser than 1 mm is mixed with tap-hole loam in the amount of 5-30% and is loaded into gun by first batch. When tap hole is closed, tap-hole loam is forced to hearth for forming skull on its walls in the vicinity of tap hole. Used as skull-forming additive is silicon carbide and/or shungite. Skull-forming additive is introduced into hearth through all tap holes according to results of monitoring lining temperature at joint of hearth wall and blast furnace bottom at positive deflection of average temperature of hearth lining from preset level by more than 10 C. At monitoring hearth lining temperature by sectors and revealing the sector at maximum temperature, skull-forming additive is introduced into hearth through tap hole in sector having maximum temperature at deviation from average temperature over circumference of hearth by more than 15 C. EFFECT: enhanced efficiency of protective skull; increased campaign of furnace. 3 cl, 2 ex